Tension device for grain binders



June 26, 1934. B. R. BENJAMIN TENSION DEVICE FOR GRAIN BINDERS Filed June 22. 19551 Patentecl `lune 26, 1934 UNITED STATES PATENT OFFICE Bert R. Benjamin, Oak Park, Ill., assignor to International Harvester Company, a corporation of New Jersey Application June 22, 1931, Serial No. 545,889

3 Claims.

The invention relates to an improved tension device for grain binders.

These devices, as well known in the art, are arranged between the twine can and needle to facilitate handling of the twine by preventing undue slack therein, to overcome the possibility of its snarling and tangling. Slack arms have also been associated with these tension devices.

It has been found that certain objections are inherent in devices of this kind, in that, especially When the pull on the twine is abnormally great, the twine breaks because the grip of the tension device remains constant.

The object of this invention is to utilize the slack arm to transmit the force of abnormal pull on the twine to move means that will automatically release the grip of the tension device so that, under such condition, the twine will be run out to the needle easily, thereby overcoming possibility of its breakage.

Another object is to provide an automatically acting tension release for a device of the kind stated when an abnormal pull occurs in the twine.

Other objects will be apparent to those skilled in this art as the disclosure is more fully made.

In the accompanying sheet of drawings illustrating a practicable embodiment of the invention by way of example,-

Figure 1 is a side elevational view of the improved tension device mounted on the twine can;

Figure 2 is a similar view, showing the positions relatively assuxned by the parts when the tension has been released by the slack arm;

Figure 3 is a front elevational view of the device; and,

Figure 4 is a top plan view thereof.

For purposes of illustration, the improved tenson device is shown mounted on the twine can 10 of a grain binder. The tension device comprises the several parts now to be described.

The upper part of the can has riveted thereto a bracket 11 that turnably carries a pin 12, upon which is mounted a turnable corrugated roller 13. The lower portion of the bracket includes a laterally projecting fiat extension 14 embodyng an eye 15 for a purpose later to appear. An end of the pin 12 projects laterally of the bracket 11, as best appears in Figures 3 and 4. Such projected end has rigidly fitted thereinto in the manner shown, the upper end of a wire slack arm 16, the lower end of which is twisted into an eye portion 17. Thus. the slack arm is disposed at one side of the bracket 11, but toward its lower end it is bent inwardly, so that the eye 1'7 will be centrally disposed substantially beneath the eye 15 heretofore described. The upper portion of the slack arm 16 adjacent its anchorage in the pin 12 is fastened, preferably by welding, to one edge of a rectangularly shaped plate or block 18 formed with curled wiper edge 19 at its opposite Side, which edge is continued, as shown, to form a Wing 20. This Wing is provided with a series of spaced holes 21, any selected one of which may serve as the point of connection for a spring 22. The other end of this spring 22 is anchored to an eyed bracket 23 secured at any appropriate point to the twine can 10.

The strand of twine is shown at 24, the same being run through a passage 25 in the upper end of bracket 11 and through the usual opening in the upper end of the twine can, not shown.

The upper end of bracket 11 is formed with two laterally projecting ears 26 for carrying a hinge pin 27, to which is hingedly, or pivotally, attached a depending outer bracket 28. This bracket 28 comprises spaced side members which adjacent their lower ends journal a pin 29 that carries a corrugated roller 30 to mesh with roller 13 already described. Thus, it will be seen that the strand of twine must pass between the two rollers 13, 30 in such a manner as to be gripped between the meshed corrugations of these rollers.

These rollers 13, 30 are tensioned by being resiliently pressed together through the mediary of a compressed spring 31 encircling a bolt 32 carried by the upper portion of the outer bracket 28, as best shown in Figures 1 and 3. By means of a nut 33, the spring compression may be adjustably set. outer bracket 28 is thus resisted and, as a result, the two rollers 13, 30 are resiliently pressed together to tension the twine running therebetween. The operation of the device will now be described.

In accordance with the demand of the binder needle and knotter mechanism, the strand of twine 24 is run out of the top of the can 10 through passage 25 in bracket 11; thence between the resiliently pressed rollers 13, 30, which tension the twine to prevent snarling thereof. Next, it is passed through the eye 15. If slack develops beyond the tension. device, it will be supported by the slack arm 16 as the twine runs through the eye 17 thereof.

Should the pull of the twine through the tension device be abnormally strong for any reason, there exists a great possibility of breaking the twine unless the tension of the roller grip be released. Accordingly, such abnormal pull causes the slack Outward hinging movement of the arm 16 to swing back to the left, as shown in Figure 2, causing the plate, or rather its wiper surface 19, to engage and ride along the edge of pin 29, which projects laterally of bracket 28 for this purpose. Continued movement thereupon causes outer bracket 28 to be hinged outwardly against the force of spring 31, to separate or unmesh rollers 13, 30, whereupon the twine may momentarily, or at least until the abnormal pull condition has disappeared, pass freely through the tension device free of any tension. When conditions are again normal, the light spring 22 returns the slack arm 16 and member 18 to normal position, as shown in Figure l, and the tension device once more functions normally.

From this description, it is now apparent that an improved tension device for grain binders has been provided, which achieves all of the desirable objects heretofore recited.

It is the intention to cover herein all such changes and modifications which do not depart from the spirit and scope of the invention as defined in the following claims.

What is claimed is:

1, A twine tension device for grain binders comprising, in combination, a stationary bracket adapted for mounting on a support, a corrugated roller rotatably carried by the bracket, a second bracket hingedly connected to the first bracket, a corrugated roller rotatably carried by the second bracket, said rollers meshing to grip the strand of twine passed therebetween, spring means resiliently pressing the rollers together, a slack arm connected to the stationary bracket and provided with means to support the twine, a block secured to the slack arm near its point of connection to the stationary bracket, said block engaging the hinged bracket when an abnormal pull occurs on the twine to separate the brackets and rollers to release the tension on the twine.

2. A twine tension device for grain binders comprising, in combination, a stationary bracket adapted for mounting on a suitable support, a movable bracket hingedly connected to the stationary bracket, means resiliently pressing the brackets together, each bracket carrying a pin, a roller mounted on each pin, said rollers receiving the twine therebetween to tension the same, and a slack arm anchored to the pin on the stationary bracket, said slack arm having a plate secured thereto and provided with an edge adapted to engage the pin on the movable bracket to separate the brackets and rollers to release the tension on the twine when the slack arm is moved on one direction under the force of an abnormal pull on the twine.

3. A twine tension device for grain binders comprising, in combination, a stationary bracket adapted for mounting on a suitable support, a movable bracket hingedly connected to the stationary bracket, means resiliently pressing the brackcts together, each bracket carrying a pin, a roller mounted on each pin, said rollers receiving the twine therebetween to tension the same, a slack arm anchored to the pin on the stationary bracket, said slack arm having a plate secured thereto and provided with an edge adapted to engage the pin on the movable bracket to separate the brackets and rollers to release the tension on the twine when the slack arm is moved in one direction under the force of an abnormal pull on the twine, and means to return the slack arm and plate to normal position.

BERT R. BENJAMIN. 

